Skip to main content Accessibility help

Grass silage particle size when fed with or without maize silage alters performance, reticular pH and metabolism of Holstein-Friesian dairy cows

  • U. Tayyab (a1), R. G. Wilkinson (a1), G. L. Charlton (a1), C. K. Reynolds (a2) and L. A. Sinclair (a1)...


The particle size of the forage has been proposed as a key factor to ensure a healthy rumen function and maintain dairy cow performance, but little work has been conducted on ryegrass silage (GS). To determine the effect of chop length of GS and GS:maize silage (MS) ratio on the performance, reticular pH, metabolism and eating behaviour of dairy cows, 16 multiparous Holstein-Friesian cows were used in a 4×4 Latin square design with four periods each of 28-days duration. Ryegrass was harvested and ensiled at two mean chop lengths (short and long) and included at two ratios of GS:MS (100:0 or 40:60 dry matter (DM) basis). The forages were fed in mixed rations to produce four isonitrogenous and isoenergetic diets: long chop GS, short chop GS, long chop GS and MS and short chop GS and MS. The DM intake (DMI) was 3.2 kg/day higher (P<0.001) when cows were fed the MS than the GS-based diets. The short chop length GS also resulted in a 0.9 kg/day DM higher (P<0.05) DMI compared with the long chop length. When fed the GS:MS-based diets, cows produced 2.4 kg/day more (P<0.001) milk than when fed diets containing GS only. There was an interaction (P<0.05) between chop length and forage ratio for milk yield, with a short chop length GS increasing yield in cows fed GS but not MS-based diets. An interaction for DM and organic matter digestibility was also observed (P<0.05), where a short chop length GS increased digestibility in cows when fed the GS-based diets but had little effect when fed the MS-based diet. When fed the MS-based diets, cows spent longer at reticular pH levels below pH 6.2 and pH 6.5 (P<0.01), but chop length had little effect. Cows when fed the MS-based diets had a higher (P<0.05) milk fat concentration of C18 : 2n-6 and total polyunsaturated fatty acids compared with when fed the GS only diets. In conclusion, GS chop length had little effect on reticular pH, but a longer chop length reduced DMI and milk yield but had little effect on milk fat yield. Including MS reduced reticular pH, but increased DMI and milk performance irrespective of the GS chop length.


Corresponding author


Hide All
Agriculture and Horticulture Development Board 2017. Statistics of the UK dairy industry. Retrieved on 18 July 2017 from
Association of Official Analytical Chemists 2012. Official methods of analysis, 19th edition. AOAC, Arlington, VA, USA.
Chilliard, Y, Ferlay, A, Mansbridge, RM and Doreau, M 2000. Ruminant milk fat plasticity: nutritional control of saturate, polyunsaturated, trans and conjugated fatty acids. Annals of Zootechnology 49, 181205.
Ferguson, JD, Galligan, DT and Thomsen, N 1994. Principal descriptors of body condition score in Holstein cows. Journal of Dairy Science 77, 26952703.
Hart, KJ, Huntingdon, JA, Wilkinson, RG, Bartram, CG and Sinclair, LA 2015. The influence of grass silage-to-maize silage ratio and concentrate composition on methane emissions, performance and milk composition of dairy cows. Animal 9, 19.
Kammes, KL and Allen, MS 2012. Nutrient demand interacts with grass particle length to affect digestion responses and chewing activity in dairy cows. Journal of Dairy Science 95, 807823.
Khan, NA, Peiqiang, Y, Mubarak, A, Cone, JW and Hendricks, WH 2015. Nutritive value of maize silage in relation to dairy cow performance and milk quality. Journal of the Science of Food and Agriculture 96, 238252.
Kliem, KE, Morgan, R, Humphries, DJ, Shingfield, KJ and Givens, DI 2008. Effect of replacing grass silage with maize silage in the diet on bovine milk fatty acid composition. Animal 2, 18501858.
Kononoff, PJ and Heinrichs, AJ 2003. The effect of reducing alfalfa haylage particle size on cows in early lactation. Journal of Dairy Science 86, 14451457.
Kononoff, PJ, Heinrichs, AJ and Lehman, HA 2003. The effect of corn silage particle size on eating behaviour, chewing activities and rumen fermentation in lactating dairy cows. Journal of Dairy Science 86, 343353.
March, MD, Haskell, MJ, Chagunda, MGG, Langford, FM and Roberts, DJ 2014. Current trends in British dairy management regimens. Journal of Dairy Science 97, 79857994.
Martin, P and Bateson, P 2007. Measuring behaviour. Cambridge University Press, Cambridge, UK.
McDonald, P, Henderson, AR and Heron, SJE 1991. The biochemistry of silage. Chalcombe Publications, Marlow, Bucks, UK.
Mertens, DR 1997. Creating a system for meeting the fiber requirements of dairy cows. Journal of Dairy Science 80, 14631481.
McCleary, BV, Gibson, TS and Mugford, DC 1997. Measurement of total starch in cereal products by amyloglucosidase-alpha-amylase method: collaborative study. Journal of AOAC International 80, 571579.
Mulligan, FJ, Quirke, J, Rath, M, Caffrey, PJ and O’Mara, FP 2002. Intake, digestibility, milk production and kinetics of digestion and passage for diets based on maize or grass silage fed to late lactation dairy cows. Livestock Production Science 74, 113124.
Nasrollahi, SM, Imani, M and Zebeli, Q 2015. A meta-analysis and meta-regression of the effect of forage particle size, level, source, and preservation method on feed intake, nutrient digestibility, and performance in dairy cows. Journal of Dairy Science 98, 89268939.
Oba, M and Allen, MS 2003. Effects of corn grain conservation method on feeding behavior and productivity of lactating dairy cows at two dietary starch concentrations. Journal of Dairy Science 86, 174183.
O’Mara, FP, Fitzgerald, JJ, Murphy, JJ and Rath, M 1998. The effect on milk production of replacing grass silage with maize silage in the diet of dairy cows. Livestock Production Science 55, 7987.
Offner, A, Bach, A and Sauvant, D 2003. Quantitative review of in situ starch degradation in the rumen. Animal Feed Science and Technology 106, 8193.
Plaizier, JC, Krause, DO, Gozho, GN and McBride, BW 2008. Subacute ruminal acidosis in dairy cows: The physiological causes, incidence and consequences. The Veterinary Journal 176, 2131.
Sinclair, KD, Garnsworthy, PC, Mann, GE and Sinclair, LA 2014. Reducing dietary protein in dairy cow diets: implications for nitrogen utilization, milk production, welfare and fertility. Animal 8, 262274.
Sinclair, LA, Edward, R, Errington, KA, Holdcroft, AM and Wright, M 2015. Replacement of grass and maize silages with lucerne silage; effects on performance, milk fatty acid profile and digestibility in Holstein-Friesian dairy cows. Animal 9, 19701978.
Soita, HW, Fehr, M, Christensen, DA and Mutsvangwa, T 2005. Effect of corn silage particle length and forage: concentrate ratio on milk fatty acid composition in dairy cows fed supplemental flaxseed. Journal of Dairy Science 88, 28132819.
Tafaj, M, Zebeli, Q, Baes, C, Steingass, H and Drochner, W 2007. A meta-analysis examining effects of particle size of total mixed rations on intake, rumen digestion and milk production in high-yielding dairy cows in early lactation. Animal Feed Science and Technology 138, 137161.
Tayyab, U, Wilkinson, RG, Reynolds, CK and Sinclair, LA 2017. Particle size and physically effective fibre (peNDF) distribution in a range of grass silage, maize silage and total mixed rations on UK dairy herds. Advances in Animal Biosciences 8, 73.
Tayyab, U, Wilkinson, RG, Reynolds, CK and Sinclair, LA 2018. Grass silage particle length and grass to maize silage ratio effects on production and reticulo-rumen pH in dairy cows. Advances in Animal Biosciences 9, 159.
Thomas, C ed.) 2004. Feed into milk. A new applied system for dairy cows: an advisory manual. Nottingham University Press, Nottingham, UK.
Van Keulen, J and Young, BA 1977. Evaluation of acid-insoluble ash as a natural marker in ruminant digestibility studies. Journal of Animal Science 44, 282287.
Van Soest, PJ, Robertson, JB and Lewis, BA 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. Journal of Dairy Science 74, 35833597.
Yang, WZ and Beauchemin, KA 2007. Altering physically effective fiber intake through forage proportion and particle length: Digestion and milk production. Journal of Dairy Science 90, 34103421.
Zebeli, Q, Aschenbach, JR, Tafaj, M, Boghun, J, Ametaj, BN and Drochner, W 2012. Review: role of physically effective fiber and estimation of dietary fiber adequacy in high-producing dairy cattle. Journal of Dairy Science 95, 10411056.
Zebeli, Q, Tafaj, M, Weber, I, Dijkstra, J, Steingass, H and Drochner, W 2007. Effects of varying dietary forage particle size in two concentrate levels on chewing activity, ruminal mat characteristics, and passage in dairy cows. Journal of Dairy Science 90, 19291942.


Type Description Title
Supplementary materials

Tayyab et al. supplementary material 1
Tayyab et al. supplementary material

 Word (44 KB)
44 KB


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed